Array trays and assemblies are used in analyzing liquids and solids to determine, for example, their chemical, biochemical, or biological nature (including, for example, DNA/RNA cleanups, PCR setup, protein precipitation, solid phase extraction, protein purification, solubility assays, kinase assays, solid-liquid extraction, protein separation, and cell-based assays). Such arrays include filter plates and solid phase extraction (SPE) plates, which typically contain a plurality of wells in which liquids are forced through a membrane or sorbent located at the bottom of each well using differential pressure across the well.
Conducting assays using these multiwell plates generally requires multiple additions of liquids into the wells in the plates alternating with removal of the liquids. During an assay, non-soluble material in the liquid may cause a blockage (also referred to as a “clog”) that prevents the liquid from migrating through the well at the preferred rate over the desired period of time, resulting in a clogged well (also referred to as a “blocked” well). Clogged wells can overflow with the subsequent addition of liquid, causing loss of the samples in the clogged wells as well as contamination of the surrounding wells.
It would, therefore, be desirable to have methods and systems for determining the fill-ready status of each well in a filter or SPE plate in order to detect any clogged well in a filter or SPE plate and protect against sample loss and contamination.